transform_crs: Transform between Coordinate Reference Systems

In Ostluft/rOstluft: Tools for handling air quality data by Ostluft

Transform between Coordinate Reference Systems

Description

Transform between Coordinate Reference Systems

Usage

transform_crs(data, coord, in_crs, out_crs, append = TRUE)

transform_LV95_to_WSG84(data, coord = c(lon = "x", lat = "y"), append = TRUE)

transform_WSG84_to_LV95(data, coord = c(x = "lon", y = "lat"), append = TRUE)

transform_LV03_to_WSG84(data, coord = c(lon = "x", lat = "y"), append = TRUE)

transform_WSG84_to_LV03(data, coord = c(x = "lon", y = "lat"), append = TRUE)

Arguments

data	input data
coord	mappping of columns for Conversion
in_crs	source coordinate reference system as sp::CRS
out_crs	target coordinate reference system as sp::CRS
append	append data in new Columns

Value

tibble with transformed coordinates

WSG84 (EPSG 4326) vs Web Pseudo Mercator (EPSG 3857)

See Tiles à la Google Maps for a detailed explanation. In Short:

EPSG:4326 uses a coordinate system on the surface of a sphere or ellipsoid of reference.

EPSG:3857 uses a coordinate system PROJECTED from the surface of the sphere or ellipsoid to a flat surface.

Usually Packages and Webservices expects coordinates for Elements in EPSG:4326, one Exception is leaflet::addRasterImage()

Known Issues

R spatial is migrating to PROJ6+ and gdal3+. At the moment the sp::spTransform isn't converted to use the WKT comments, and rgdal raises some Warnings. The transformation are done correctly.

• R spatial follows GDAL and PROJ development

• Migration to PROJ6/GDAL3

• rOstluft Issue

See Also

• sp::spTransform()

• sp::proj4string()

• sp::CRS

• PROJ4

• epsg.io: Coordinate Systems Worldwide

• Working with projections in Leaflet

• Tiles à la Google Maps

Examples

fn <- system.file("extdata", "meta_smn.rds", package = "rOstluft.data")
data <- readRDS(fn)
data <- dplyr::distinct(data, site, x, y)
transform_crs(
  data = data,
  coord = c(lon = "x", lat = "y"),
  in_crs = sf::st_crs("EPSG:2056"),
  out_crs = sf::st_crs("EPSG:4326")
)

transform_crs(
  data = data,
  coord = c(lon = "x", lat = "y"),
  in_crs = sf::st_crs("EPSG:2056"),
  out_crs = sf::st_crs("EPSG:4326"),
  append = FALSE
)

transform_LV95_to_WSG84(data)

Ostluft/rOstluft documentation built on Feb. 6, 2024, 1:26 a.m.